Human Auditory Neurons More Sensitive Than Those Of Other Mammals
The human ear is exquisitely tuned to discern different sound frequencies, whether such tones are high or low, near or far. But the ability of our ears pales in comparison to the remarkable knack of single neurons in our brains to distinguish between the very subtlest of frequency differences.
Reporting in the Jan. 10 issue of the journal Nature, Dr. Itzhak Fried, professor of neurosurgery and director of the UCLA Epilepsy Surgery Program, and colleagues from Hebrew University and the Weizmann Institute of Science in Israel, show that in humans, a single auditory neuron in the brain exhibits an amazing selectivity to a very narrow sound-frequency range, roughly down to a tenth of an octave.
In fact, the ability of such neurons to detect the slightest of differences in sound frequency far surpasses that of the human auditory nerve, which carries information from the hair cells of the inner ear to the brain's auditory cortex